In the Linux kernel, the following vulnerability has been resolved:
net/handshake: hand off the pinned file reference to accept_doit
handshake_req_next() removes the request from the per-net
pending list and drops hn_lock before handshake_nl_accept_doit()
reads req->hr_sk->sk_socket and dereferences sock->file (once in
FD_PREPARE() and again in get_file()). In that window a
consumer running tls_handshake_cancel() followed by sockfd_put()
(svc_sock_free) or __fput_sync() (xs_reset_transport) releases
sock->file. sock_release() then runs sock_orphan(), zeroing
sk_socket, and frees the struct socket. The accept-side code
either reads NULL through sk_socket or chases freed memory.
The submit-side sock_hold() does not prevent this. sk_refcnt
protects struct sock, but struct socket and sock->file are
independently refcounted via the file descriptor the consumer
owns. Pinning sk leaves sock and sock->file unprotected.
Retarget the accept-side dereferences at req->hr_file, which was
pinned at submit time, instead of req->hr_sk->sk_socket->file.
Pinning on its own is not sufficient: a consumer that cancels
between handshake_req_next() returning and accept_doit reaching
FD_PREPARE() takes the !remove_pending() branch in
handshake_req_cancel() and drops hr_file before the accept side
takes its own reference. Hand off an additional file reference
inside handshake_req_next(), under hn_lock, so the accept side
operates on a reference that no concurrent handshake_req_cancel()
can revoke. FD_PREPARE() consumes that handed-off reference,
either by transferring it to the new fd in fd_publish() or by
dropping it in the cleanup destructor on error; the explicit
get_file() that previously balanced FD_PREPARE() is therefore
redundant and goes away.
Update handshake_req_cancel_test2 and _test3 to simulate the
FD_PREPARE() consumption with an fput() so the kunit file-count
assertions stay balanced.
References
Configurations
Configuration 1 (hide)
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History
12 Nov 2026, 18:46
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* |
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| First Time |
Linux linux Kernel
Linux |
|
| References | () https://git.kernel.org/stable/c/2f28dbb30b88eafab8d49aaec94710b4e12dea8e - Patch | |
| References | () https://git.kernel.org/stable/c/68eba6519cbd6359fb554a9720f3a3b6b2eba23f - Patch | |
| References | () https://git.kernel.org/stable/c/b869e3e4ce1996df23b3efdbbe9a64c4ab81d745 - Patch | |
| References | () https://git.kernel.org/stable/c/c06876d4fac38f35820946ee3b1be7d7da799cd4 - Patch | |
| References | () https://git.kernel.org/stable/c/f4251190e58b209999c1ba9e6d2976136a1be055 - Patch |
21 Oct 2026, 13:19
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
19 Oct 2026, 21:17
| Type | Values Removed | Values Added |
|---|---|---|
| CWE | CWE-416 |
Information
Published : 2026-07-19 16:17
Updated : 2026-11-12 18:46
NVD link : CVE-2026-63979
Mitre link : CVE-2026-63979
CVE.ORG link : CVE-2026-63979
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-416
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